The Link Layer Discovery Protocol (LLDP) is a vendor-neutral link layer protocol used by network devices for advertising their identity, capabilities, and neighbors on a local area network based on IEEE 802 technology, principally wired Ethernet.
The topology of an LLDP-enabled network can be discovered by crawling the hosts and querying this database.
Media Endpoint Discovery is an enhancement of LLDP, known as LLDP-MED, that provides the following facilities: The LLDP-MED protocol extension was formally approved and published as the standard ANSI/TIA-1057 by the Telecommunications Industry Association (TIA) in April 2006.
[4] LLDP information is sent by devices from each of their interfaces at a fixed interval, in the form of an Ethernet frame.
The basic format for an organizationally specific TLV is shown below: According to IEEE Std 802.1AB, §9.6.1.3, "The Organizationally Unique Identifier shall contain the organization's OUI as defined in IEEE Std 802-2001."